Four Archaean cratons (Aravalli–Bundelkhand, Singhbhum, Bastar and Dharwar), together with the marginal Proterozoic mobile belts and sedimentary basins, constitute the geology of peninsular India. Huge resources of ferrous metals (Fe and Mn) and chromite, the lone granitoid-hosted Malanjkhand Cu–Mo deposit, a moderate occurrence of gold and promising platinum group element mineralization constitute the Archaean metal inventory of India. Additionally, the Proterozoic Aeon witnessed diverse mineralization in the mobile belts and craton–mobile belt contacts. These include vast resources of base metals in the northwestern Indian Shield and Mn in the central Indian block, apart from considerable U–Cu deposits in the Singhbhum Shear Zone. These ores formed as a consequence of an entire genetic spectrum, covering various orthomagmatic, volcanosedimentary and diverse hydrothermal processes, aided and abetted by supergene enrichment, as in the case of iron ores.
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Precambrian Basins of India: Stratigraphic and Tectonic Context
This Memoir provides a comprehensive review of the Precambrian basins of the four Archaean nuclei of India (Dharwar, Bastar, Singhbhum and Aravalli-Bundelkhand), encompassing descriptions of the time–space distribution of sedimentary–volcanic successions, the interrelationship between tectonics and sedimentation, and basin histories. Studies of 22 basins within the framework of an international basin classification scheme deepen an understanding of the basin architecture especially for cratonic basins. Most Indian sedimentary successions formed as cratonic to extensional-margin rift and thermal-sag basins, some reflecting mantle plume movement, subcrustal heating or far-field stress. This Memoir shows that Phanerozoic plate-tectonic and sequence stratigraphic principles can be applied to the Precambrian basins of large Archaean provinces. The differences between the stratigraphic architecture of the Indian Precambrian and examples of Phanerozoic basin-fill successions elsewhere are ascribed to variable rates and intensities of the controls on accommodation and sediment supply, and changes inherent in the evolution of the hydrosphere–atmosphere and biosphere systems.